I've been on Seroquel before. It made me physically lethargic and slowed my mental processes. At any dose, it reduced my anxiety by about the same amount that it reduced my ability to cope with the anxiety, so it didn't really produce a net benefit. It more or less just shuts everything down equally. Like you I would oversleep and be groggy all day. I have taken it with benzodiazepines like diazepam or alprazolam, and this increases its effect by a very large amount. Benzodiazepines by themselves reduced my anxiety and inhibition without making me really groggy, but they are pretty addictive and when you withdraw from them the anxiety shoots way up. I've been on other antipsychotics for anxiety and they all produce about the same effects as Seroquel. In my case I found them not to be useful.